New Delhi: Sky gazers are in for a double celestial treat on the evening of the Republic Day as Venus and Moon will converge in for a beautiful conjunction, apart from seeing our natural satellite's ashen glow.

"Moon's ashen glow or 'the old Moon in the new Moon's arms' takes place when sunlight is reflected from the Earth to one side of the Moon due to which it appears to glow faintly and the entire orb of the satellite is dimly visible," said Director of Nehru Planetarium (Nehru Centre) Arvind Paranjpye.

The phenomenon is also known as Earthshine, SPACE Director C B Devgun said.

"The glow on the dark portion of the crescent Moon is known as earthshine," he said.

Apart from the moon's ashen glow, astro-enthusiasts will also be able to witness a conjunction of thin crescent Moon and Venus tomorrow night.

"Venus can be seen shining brilliantly above the western horizon after the sunset," Paranjpye said.

Conjunction, also known as appulse, is a phenomenon in which celestial bodies appear near one another as seen from the Earth.

"The bright pair of the planet and the moon can be seen with naked eyes," Planetary Society of India General Secretary N Sri Raghunandan Kumar said.

Both the Moon and the Venus will appear very near to each other, he said.